diff --git a/magrep.c b/magrep.c
index 6f93a57..72ce1bb 100644
--- a/magrep.c
+++ b/magrep.c
@@ -7,6 +7,7 @@
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
+#include <strings.h>
 #include <unistd.h>
 
 #include "blaze822.h"
diff --git a/mdeliver.c b/mdeliver.c
index 161cea5..27c4b9c 100644
--- a/mdeliver.c
+++ b/mdeliver.c
@@ -10,6 +10,7 @@
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
+#include <strings.h>
 #include <unistd.h>
 
 #include "blaze822.h"
diff --git a/mflow.c b/mflow.c
index af6755d..1013da5 100644
--- a/mflow.c
+++ b/mflow.c
@@ -7,6 +7,7 @@
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
+#include <strings.h>
 #include <unistd.h>
 
 #include "blaze822.h"
diff --git a/mhdr.c b/mhdr.c
index d434d1d..83bed02 100644
--- a/mhdr.c
+++ b/mhdr.c
@@ -7,6 +7,7 @@
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
+#include <strings.h>
 #include <unistd.h>
 
 #include "blaze822.h"